<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    #app {
      width: 500px;
      height: 1500px;
      background-color: pink;
      margin-left: 50px;
    }
  </style>
</head>

<body>
  <div id="app"></div>
  <script src="./6.x.eventx.offsetx.js"></script>
</body>

</html>